This invention concerns an electrical connector, or coupling, which includes a connecting lug formed as a tongue-shaped metal plate which has a substantially slit-shaped recess for holding a wire.
Such an electrical connector is, for example, disclosed in German Offenlegungsschrift DE-OS 2 339 041 in which a slit-shaped recess of a connecting lug is formed by a blade, or cutting edge.
When an insulated wire lead is shoved into the recess, the recess edge cuts into the insulation and clamps the wire lead tightly, thereby providing a mechanical connection as well as an electrical connection to the wire lead. For this reason such connectors, or couplings, are sometimes called cut-clamp connectors.
Because recesses of such connectors are generally manufactured by punch machines, the recess cannot, because of technical manufacturing reasons, be narrower than a material thickness of the connecting lug (otherwise, the punching tool must be so thinly constructed that it is mechanically less stable than the work piece to be punched).
It follows from this that the connector of the prior art, which should exhibit a particular mechanical stability, has the disadvantage of only being able to hold wire leads with relatively large cross sections; or conversely, that connectors for receiving wires with small cross sections must have particularly thin walls and be mechanically unstable.
With known cut-clamp connectors the recesses are enlarged by wire leads which are shoved therein. A clamping force which is thereby created fixes the wire with a force fit, by means of static friction. From a stand point of providing a particularly good electrical and mechanical connection, it would be desirable to have a shape-, or form-, interlock; or better yet, an additional shape-interlock connection between the wire lead and the connecting lug.
It is therefore an object of this invention to provide an electrical connector which is relatively easy and cost effective to manufacture and which makes possible a particularly reliable and electrically and mechanically strong connection between a wire and a connecting lug; and with which a cross section of the wire can be substantially smaller than a thickness of the connecting lug.